It is known to provide a hermetically sealed, current conducting terminal assembly that can be installed in a housing to provide an electrical connection through a wall of the housing, while electrically isolating the terminal assembly from the housing. Such terminal assembly incorporates a current conducting terminal pin, the outer segment of the pin being connected to an electrical power source and the inner segment of the pin being hermetically confined within the housing and connected to a device within the housing, such as a sealed motor unit, for example.
As shown in FIG. 8, a plurality of terminal assemblies 10 are extending through a housing plate 12 and walled housing 14. The housing plate 12 and walled housing 14 include a series of attachment apertures 16 and accompanying fasteners 18 for attaching the housing plate 12 to the walled housing 14. In addition, the housing plate 12 and walled housing 14 include a plurality of coaxially aligned threaded bores 20 for mating engagement with the terminal assemblies 10.
The terminal assemblies 10 are received by the threaded bores 20 of the housing plate 12 and walled housing 14. One terminal assembly arrangement can be found in U.S. Pat. No. 5,227,587, issued on Jul. 13, 1993 to F. Dieter Paterek, the general arrangement being particularly adapted to hermetically sealed housings. As shown in FIG. 9, the hermetic terminal assembly 10 of Paterek includes an annular sleeve 26, a hermetic seal 28, a pair of insulating annular ceramic sleeves 30, and a current conducting pin 32. The annular sleeve 26 includes a series of threads 34 for attaching the terminal assembly 10 to a threaded bore 20 of a housing plate 12 or walled housing 14. The current conducting pin 32 comprises a unitary body having a first threaded end 36 and a second threaded end 38. The first threaded end 36 and second threaded end 38 are operable to connect to an external source generally disposed outside of the walled housing 14 and an internal source disposed within the walled housing 14, respectively.
The hermetic seal 28 and annular ceramic sleeves 30 electrically isolate the current conducting pin 32 from the annular sleeve 26. In this regard, the hermetic seal 28 and annular ceramic sleeves 30 allow the current conducting pin 32 to transmit electricity into and out of the walled housing 14 without transmitting electricity to the housing wall 40.
The terminal assemblies described above may be comparatively expensive and difficult to manufacture. Therefore, a hermetically sealed terminal assembly that is easier and less expensive to manufacture while concurrently providing for the effective electrical isolation between a current conducting pin and a housing is desirable in the industry.